Analysis Of Related Factors Of Kyphosis After Removal Of Internal Fixation For Burst Fractures Of Thoracolumbar Segment

Objective:According to the analysis of imaging parameters,to study whether the thoracolumbar burst fracture recurs after removal and internal fixation and its related influencing factors,and hope to find relevant indicators that can indicate prognosis,and then guide clinical work.Methods:Collect the data of patients who underwent thoracolumbar burst fractures and internal fixation after bone healing from January 2016 to January 2020 in our hospital,and obtained age,gender,and vertebral wedge angle(vertebral wedge angle,VWA),anterior vertebral height ratio(AVH),upper intervertebral angle(UIVA),lower intervertebral angle(LIVA),regional angle(RA),Cobb angle(CA),sagittal index(SI)and Denis score.The abovementioned imaging parameters were measured before operation,after operation,before removing the internal fixation and at the final follow-up.Observe the recurring kyphosis and analyze the relationship with other image parameters.Results:After surgical correction,the height of the vertebral body(the ratio of the anterior edge height of the vertebral body and the wedge angle of the vertebral body)remained stable until the final follow-up,while the intervertebral disc space(upper and lower intervertebral angle)collapsed,resulting in progressive kyphosis(Cobb angle,Regional angle and sagittal index).In the end,there was no significant correlation between kyphosis and pain.However,18 patients with sagittal index> 15° had a higher incidence of moderate to severe pain compared with the remaining 44 patients with sagittal index <15° High(Denis score 3-5 points).Recurrent kyphosis was significantly correlated with the height ratio of the anterior edge of the vertebral body(r =-0.777,p<0.001).Conclusion:The loss of surgical correction mainly occurs through the collapse of the intervertebral disc.The final degree of kyphosis can be predicted by the degree of postoperative fractured vertebral height recovery observed in lateral X-rays.Surgeons try to restore the height of the fractured vertebral body to a complete state when performing posterior reduction and fixation operations.